Workers at a factory produces toy with a defect about once every 4 hours on average. a.

Question:

Workers at a factory produces toy with a defect about once every 4 hours on average.
a. What is the probability there will be exactly 5 defects in 24 hours?
b. What is the probability that there will be exactly 5 defects in each of the next seven 24-hour periods?
c. What is the probability there will be a total of 5 × 7 = 35 defects in the next week (168 hours)? Why is this answer different from part b?